mobile/android/base/sync/crypto/PBKDF2.java@6474c204b198 (annotated)
mobile/android/base/sync/crypto/PBKDF2.java
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
| michael@0 | 1 | /* This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 2 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
| michael@0 | 3 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| michael@0 | 4 | |
| michael@0 | 5 | package org.mozilla.gecko.sync.crypto; |
| michael@0 | 6 | |
| michael@0 | 7 | import java.security.GeneralSecurityException; |
| michael@0 | 8 | import java.util.Arrays; |
| michael@0 | 9 | |
| michael@0 | 10 | import javax.crypto.Mac; |
| michael@0 | 11 | import javax.crypto.ShortBufferException; |
| michael@0 | 12 | import javax.crypto.spec.SecretKeySpec; |
| michael@0 | 13 | |
| michael@0 | 14 | public class PBKDF2 { |
| michael@0 | 15 | public static byte[] pbkdf2SHA256(byte[] password, byte[] salt, int c, int dkLen) |
| michael@0 | 16 | throws GeneralSecurityException { |
| michael@0 | 17 | final String algorithm = "HmacSHA256"; |
| michael@0 | 18 | SecretKeySpec keyspec = new SecretKeySpec(password, algorithm); |
| michael@0 | 19 | Mac prf = Mac.getInstance(algorithm); |
| michael@0 | 20 | prf.init(keyspec); |
| michael@0 | 21 | |
| michael@0 | 22 | int hLen = prf.getMacLength(); |
| michael@0 | 23 | |
| michael@0 | 24 | byte U_r[] = new byte[hLen]; |
| michael@0 | 25 | byte U_i[] = new byte[salt.length + 4]; |
| michael@0 | 26 | byte scratch[] = new byte[hLen]; |
| michael@0 | 27 | |
| michael@0 | 28 | int l = Math.max(dkLen, hLen); |
| michael@0 | 29 | int r = dkLen - (l - 1) * hLen; |
| michael@0 | 30 | byte T[] = new byte[l * hLen]; |
| michael@0 | 31 | int ti_offset = 0; |
| michael@0 | 32 | for (int i = 1; i <= l; i++) { |
| michael@0 | 33 | Arrays.fill(U_r, (byte) 0); |
| michael@0 | 34 | F(T, ti_offset, prf, salt, c, i, U_r, U_i, scratch); |
| michael@0 | 35 | ti_offset += hLen; |
| michael@0 | 36 | } |
| michael@0 | 37 | |
| michael@0 | 38 | if (r < hLen) { |
| michael@0 | 39 | // Incomplete last block. |
| michael@0 | 40 | byte DK[] = new byte[dkLen]; |
| michael@0 | 41 | System.arraycopy(T, 0, DK, 0, dkLen); |
| michael@0 | 42 | return DK; |
| michael@0 | 43 | } |
| michael@0 | 44 | |
| michael@0 | 45 | return T; |
| michael@0 | 46 | } |
| michael@0 | 47 | |
| michael@0 | 48 | private static void F(byte[] dest, int offset, Mac prf, byte[] S, int c, int blockIndex, byte U_r[], byte U_i[], byte[] scratch) |
| michael@0 | 49 | throws ShortBufferException, IllegalStateException { |
| michael@0 | 50 | final int hLen = prf.getMacLength(); |
| michael@0 | 51 | |
| michael@0 | 52 | // U0 = S || INT (i); |
| michael@0 | 53 | System.arraycopy(S, 0, U_i, 0, S.length); |
| michael@0 | 54 | INT(U_i, S.length, blockIndex); |
| michael@0 | 55 | |
| michael@0 | 56 | for (int i = 0; i < c; i++) { |
| michael@0 | 57 | prf.update(U_i); |
| michael@0 | 58 | prf.doFinal(scratch, 0); |
| michael@0 | 59 | U_i = scratch; |
| michael@0 | 60 | xor(U_r, U_i); |
| michael@0 | 61 | } |
| michael@0 | 62 | |
| michael@0 | 63 | System.arraycopy(U_r, 0, dest, offset, hLen); |
| michael@0 | 64 | } |
| michael@0 | 65 | |
| michael@0 | 66 | private static void xor(byte[] dest, byte[] src) { |
| michael@0 | 67 | for (int i = 0; i < dest.length; i++) { |
| michael@0 | 68 | dest[i] ^= src[i]; |
| michael@0 | 69 | } |
| michael@0 | 70 | } |
| michael@0 | 71 | |
| michael@0 | 72 | private static void INT(byte[] dest, int offset, int i) { |
| michael@0 | 73 | dest[offset + 0] = (byte) (i / (256 * 256 * 256)); |
| michael@0 | 74 | dest[offset + 1] = (byte) (i / (256 * 256)); |
| michael@0 | 75 | dest[offset + 2] = (byte) (i / (256)); |
| michael@0 | 76 | dest[offset + 3] = (byte) (i); |
| michael@0 | 77 | } |
| michael@0 | 78 | } |
